I have a list person with items and one of those items is of the type "choice".
For example:

Name (text), City (text), Favorite Artists(choice list).

Well I want to bind the title values of every listitem of another list with artists to the choicetype in the person list, but it has to update the list with choicetypes every time after someone clicks on the add button but before the add screen pops up. I tried the eventreceiver with "item being added" but then it will fire after I hit the "add" button on the item add screen but before the item was actually added.
How can I accomplish my problem.
Thank you in advance.